Here is a good article here https://www.securitycameraking.com/securityinfo/how-to-access-your-dvrnvr-without-a-router-and-access-ip-cameras-directly-with-an-nvr-with-a-built-in-poe-switch/
Also, keep in mind that you only need to power the camera with 12VDC and set your computers NIC to be on that same network and then scan using the search tool.